To resolve a recent controversy between Klein and Cleary and Levy, a model for dichotomous congeneric items is presented which has mean errors of zero, dichotomous true scores that are uncorrelated with errors, and errors that are mutually uncorrelated. (Author)

In this paper a reliable method is found for approximating the value of the Bivariate Normal Correlation Coefficient, rho, given values of the joint probability and the normal deviates, h and k, or the related areas. This technique finds useful application in the computation of the tetrachoric correlation coefficient, r, when the underlying…

The use of Bayesian statistics as the basis of classical analysis of data is described. Bayesian analysis is a set of procedures for changing opinions about a given phenomenon based upon rational observation of a set of data. The Bayesian arrives at a set of prior beliefs regarding some states of nature; he observes data in a study and then…

In this paper, a new item analysis index, e, is derived as a function of difficulty and discrimination to represent item efficiency. Item discrimination in this paper is not independent of item difficulty, and it is demonstrated algebraically that the maximum discriminating power of an item may be determined from its difficulty. Item efficiency is…

Bayesian statistical inference is unfamiliar to many educational evaluators. While the classical model is useful in educational research, it is not as useful in evaluation because of the need to identify solutions to practical problems based on a wide spectrum of information. The reason Bayesian analysis is effective for decision making is that it…

The approaches taken to psychological research are discussed. Studies are classified as axiomatic, classical, stochastic or statistical, or structural. The mathematical models used in each type of study are discussed. (SD)

The grade on a question of an answer-until-correct test is a function of the number of responses needed to find the correct response. This note considers how to assign credit for the number of responses needed to find the correct response. (Author/MP)

Ordinal measurement is the rank ordering of individuals in a population. For ordinal measurement, the concept of an individual propensity distribution is his or her true score. Estimation of, as well as other aspects of the distribution, are discussed. (Author/JKS)

A previously proposed model for memory based on neurophysiological considerations is reviewed. It is extended by introducing positive feedback of a set of neurons onto itself and allowing the neurons to saturate. The resulting model is analyzed by distinctive features, categorical perception, and as it applies to probability learning. (Editor/RK)

Available from: the Institute of Management Sciences, 146 Westminster Street, Providence, Rhode Island 02903. (JG)

In this study, the graduate school admission policy at a medium-sized, state-supported university is analyzed using a combination of Bayesian and cost/benefit decision analysis techniques. (Author)

Three exact probability tests, counterparts of t tests for single sample, independent samples, and dependent samples, are described for data obtained from ratings on "m" scales by a single rater or on a single scale by "n" raters. (LMO)

Historical problems are presented which can readily be solved by students once some elementary probability concepts are developed. The Duke of Tuscany's Problem; the problem of points; and the question of proportions, divination, and Bertrand's Paradox are included. (MNS)

The stability of standard score and probability method sociometric group assignments was examined over a two-year period with an initial group of 334 fifth graders. Popular, neglected, and controversial groups evidenced low stability of group members over intervals of approximately 1, 6, 12, 18, and 24 months. (Author/RH)

The paper presents a step-by-step procedure for finding the probability of occurrence of the difference between test scores and the probability of occurrence of errors of measurement. This procedure is useful in interpreting test results to parents and making placement decisions. Difference scores are often used in placing students in learning…